Alternating current motor control system



May 16, 1950 R. c. JONES AL'I'ERNATING CURRENT uo'roR comm. sysrzu FiledMay 26, 1944 INVENTOR Rue] C. Jones WITNESSES: W W'eluuh- ATTORNEYPatented May 16, 1950 ALTERNATING CURRENT'MOTOR CONTROL SYSTEM Ruel C.Jones, Pittsburgh, Pa, assignor to Westinghouse' Electric Corporation,Eastlittsburgh, Pa., a corporation oi Pennsylvania Application May .26,1944,8831 No.531j15 "21 Claims. (CL 318-286) My. invention relates to anelectric aircraftlaunching catapult of the type utilizing a linearmotortowing-car, and it has particular relation to. improvements in thecontrol-means therefor.

The control of a linear-motor catapult presents particularly diflicultdesign-problems because it .involves a short time, of the order of 6seconds, more-r less, a large towing-car mass, which may be of the orderof several tons, and a high maximum speed; necessary foraircraft-launching, which may 'be of the order of 90 miles per hour.more or less. Added to these problems is the danger of the possibilityof a false start, without a proper connectirn between thetowing-cableand the aircraft to be launched, and the everpresent danger of a seriouswreck, if there is any mishap during the launching or it the automaticadiustments, for predeterminin any particular launching-run, shouldprove to be wrong.

The general object of my present invention is to provide improvedcontrol-means for safeguarding the launching of aircraft with electriclinear-motor catapults.

A more specific object of my invention is..to provide improved means forresponding to any one. of a large'number of pro-selected positions ofthe car, along the length of the track, so that the. length of theaccelerating run may be predetermined or pre-selected without requiringthe utilization of. a large number of track-responsiveselector-switches. The high launching speeds frequently make impracticalthe use of simple track-switches having parts-which are adapted to bestruck by the car whenitpasses any 'par tlcular point, because theforces of such impacts, at speeds exceeding 50 miles per hour, more orless, is usually.- suchv as to overtax the strength of any readilyavailable. structural material. My present invention provides. simpleandimproved means or responding to a rare-selected one 01 a plurality ofpositions along the trackway, involving the use of a plurality o1vpositionresponsive means, for developing relaying-energy at. each oftheir several positionaduring. the progress of an aircrait-launching.acceleratingrun, a single run-controlling relay-meshe and ore-selectormeans'for making the releyinuenergy or a pro-selected one or. more of.said positionresponsive means efleetivelyavailelble .in. saidrun-controlling relay-means.

.A further object 0!. my inventionvhas todo with means for initiallyenergizing the. towingcar at a low voltage, and increasing the voltageor energlzation only after the initial energization has taken place.

With the foregoing. and other objects. in view. thy-invention, consistsof the methods. systems, circuits, combinations, structures. apparatusand parts, hereinafter described and claimed and iilustrated-in:theaccompanying.- drawing, where- .2 in the single figure is a diagrammaticview. oi circuits. and apparatus .involving my invention in anillustrative form of embodiment, with the parts not shown in properscale in order to facilitate the illustration.

My invention is illustrated in connection with an aircraft-launchingcatapult involving a selfpropelled, polyphase-motored,aircraft-launching electric towing-car I, having a towing-cable 2 and apolyphase propulsion-motor, the primary winding of which is indicated.at 3. The towing-car l .rides on rack-rails 4, along the side of whichis disposed athree-lphase third-rail bus 5a, 5b and 50. One of saidthree-phase supplybusses, 5c, is connectedto. the track-rails 4 at eachof a plurality of. spaced points along the trackway, by means .of alarge number of spaced connectors. 6. Energy forthe towing-car motor 3is supplied by. means oi current-collectors la, 'Iband 1c, makingelectrical connection, respectively, with the bus 50, the bus 5b, andthe track.

.flhe car-borne primary-winding 3 may represent any kind; ofpropulsion-motor: in a preferred form of construction, it is theprimarymember of alinear-motor. construction, as set iorth in-myapplication SeriaiNo. 500,639, filed August 31, 1943, patented December10, 1946, No. 2,4l2,5l,4, or in-an, application of- Maurice E. Jones andLee A-..Kilgore, Serial NOB-506,198, filed-October 1.4,,1943, patentedDecember 10, 1946, No. 2, 12,5l2,-and.assigned.to the WestinghouseElectric &.Manuacturing Company.

Rmpulsion-power"for the towing-car i is supplied to thethird-raiL-busses 50,51). audio from a variable-voltage three-phasesource which is shown in the. form of athree-phase synchronous generator8..wbich-is driven from any suitable prime-mover"shafts and which isprovided with exciting-field resistors R1, R2 and R3, the first two ofwhichmayhhe short-circuitedby .fleldrelays PI and- H, respectively.

In the drawing, the control is shown by schematic or fiacross the.- linediagram. The variousrrelays which areshown are of the-electromagnetic ypfi dthe same reference-character is utilized to apply tothe=relay.-coils,.showndiagrammaticallyciroles, and to .therelay-centacts,:which areJnvariably-shown in their nonenergized.positions, thus suflieiently. designating and correlating. both, parts01 each relay, that is, a both. its energizing-coil. andits-eontactfmeme ber. .01: members... or dotted. linesarenalso used. asa. ionizer-convention, for symbolically indicating how-theseriouspartsoteach relay are connected together. I speak. 'oi'anenergizing-coilrtorlaselay, I meannto reler to any. kind ofiactuating-coiiwhich causes. the reiayito. be .movediromitsnormal.position, regarded as itsnonwactuat'ed position, .to 'its ac:

3 tuated or control-responsive position, whether the actuating ormoving-force is actually produced by the relay-actuating coil. or merelycontrolled, or unlatcned, or tripped oil, by said relayactuating coil.

In the drawing, I am also showing only the circuits which seem to benecessary to convey an understanding of my present invention, omittingmany of the interlocks and safeguards and other well-known featureswhich make such control-diagrams extremely complicated, and which wouldbe readily understood and applied by any control-engineer.

The terminal leads ii of the generator 8 constitute a variable-voltagepolyphase supplymeans, the voltage of which can be controlled throughthe field-switches Fl and F2. The electrical energy of the polyphasesupply-line II is fed, in either the positive phase-sequence or thenegative phase-sequence, to the polyphase thirdrail assembly 5a, so, be,through the main contacts of either one of two main contactor-switchesor relays designated W and E respectively, contemplating, for the sakeof convenience in description, an east-and-west runway 4, with maincontactor-relays W and E for energizing the motor 3 in a phase-sequencefor developing a drivingforce in a westerly direction, or in an easterlydirection, respectively.

The power-plant shaft 8 is also illustrated as being provided with acontact-making tachometer TACH, or other speed-responsive device, whichmakes a contact 12 when the generator 8 is being driven at a speed highenough to provide adequate accelerating-power forany particularaircraft-launching operation. If desired, the contact-point l2 of thetachometer TACH may be adjustable, so as to provide for differentgenerator-speeds depending upon different startingconditions foraircraft of diflerent mass and take-off speeds. The tachometer-contactI2 is illustrated as being utilized to energize an auxiliaryspeed-responsive switch SI.

My special control-means is illustrated by various equipments which arediagrammatically indicated in the drawing. Referring to this apparatusin the order in which it appears on the drawing, reference may now bemade to a plurality of track-transformers T8 to T28 which are shown inthe form of current-transformers associated with the respectiveconnectors 8 which are spaced along the trackway at frequent intervals,for feeding power into the track-rails 4 from the third-rail Be. Whenheavy take-of! accelcrating-energy is fed into the towing-car i, thelarger part of this energy flows into the trackrails 4 at the pointwhere the car makes contact with the rails, and the current-transformersT8 to T28 are designed to develop an adequate predetermined amount ofrelaying-energy when this heavy propulsion-current is flowing throughtheir particular connectors 8.

In accordance with my invention, I provide a suitable selector-means forpre-selecting a particular one or more of the current-transformers T8 toT28, and for making its energy available for exciting a suitablerun-controlling relay-means, which is illustrated in the form of twotrackrelays TRI and TR2. Two track-relays TR! and TR2 are shown, so thatthe second track-relay can serve as a safeguard or back-up relay againsta possible failure of the first relay, the second track-relay beingenergized from the next succeeding track-transformer, selected from theroup T8 to T28. as will now be described.

Energy for the two track-relays TRI and TR2 is applied to the respectiverelay-terminals l3 and I4, respectively, by means of any suitableselector-means, which is diagrammatically indicated in the form of pushbuttons numbered PBB to P1329, which may be of the stay where put type,and which are intended to represent any selector-switch means, whetherof the pushbutton type, or of the knife-switch type, or of thedrum-type, or of the sliding-contact type, or of any other suitabletype, with any desired or suitable interlocks (not shown). The first andlast push buttons P38 and P329 are provided, as shown, with only onepair of contacts, namely a make-contact l5 and a back-contact 16. All ofthe other push buttons, PB8 to PB28 inclusive, are provided with twopairs of such contacts. In each case, the back-contact i6 is utilized ina normally closed short-circuit around one of the track-transformers T8to T28, while the corresponding front-contact I5 is utilized to connectthat particular track-transformer to one or the other of the twoterminals l3 and H of the two track-relays TR! and TR2.

The construction is such that the two and push buttons P38 and PB28,respectively, connect the track-transformers T8 and T28 to thetrack-relay TR2, so that only this single track-relay TR2 is energizedwhen the car reaches the position corresponding to the selectedtrack-relays T8 or T28, if either one of these end push buttons PB8 orP328 is depressed or selected. If any one of the intermediate pushbuttons PBS to P328 is selected, then two successive track-transformers,selected from the group T8 to T28 are connected respectively to the twotrack-relays TR! and TR2, so that both of these track-relays will beenergized, one after the other, when the car reaches the selected pointin its accelerating-run. The two track-relays TRI and TR2 thussupplement each other and make sure that at least one of them will bevery certainly operated, in response to the position of the towing-car Ialong the trackway 8.

My main direct-current control-circuits are under the control of acontrol-switch H, which energizes a control-bus C+ from the positiveterminal of any suitable direct-current control-source, the negativeterminal of which is indicated at From the control-bus C+ a circuit iscompleted to a reset-switch I9 which is capable of making either acontact 28 or a contact 2|. The contact 28 is utilized only for thepurpose oi energizing two reset-coils RSI and RSlwhich are associatedwith the respective track-relays TRI and TR2. These track-relays are ofthe position-maintaining type, which remain in whichever posltion'theyoccupy, even after the controlling-force has been removed therefrom. Thereset-coils RSI and R32 are for the purpose of causing thesetrack-relays TR! and IE2 to be reset to their normal nonactuated, ornon-selected positions, whereas the actuating-coils TRI and TR2 areutilized for the purpose of causing said track-relays to move to theiractuated or controlled or selected positions.

The other contact, 2|, of the reset-switch I 9 is the mainrelaying-contact of this switch, en ergizing a relaying bus which isdesignated by the same numeral 2|. Various relaying circuits areenergized from this relaying bus 2|. The first such circuit, shown onthe drawing, is a push-button circuit under the control of a startingswitch which is shown, diagrammatically and schematically, in the formof push button PB,

although it is to be understood'that I am not by any means limited to apush-button form 01 a starting-switch. The push button PB energizes arelay-circuit or terminal 23-01 the operailing-coil of a take-elf relayTOR, the other terminal of which is connected to the negative bus (-l Inaddition to the take-off relay TOR, I provide a direction-selecting drumDD, and an emergencydrum ED, both illustrated in the form 01' drum-typecontrollers having a central "01? position, and right-hand and left-hand.east and "west" positions.

I also provide a timer T., which is illustrated in the form of a motor,energized from a 60- cycle supply-circuit 24.

When the take-ctr relay TOR is energized, it picks up its make-contacts25, 25 and 21, immediately closing a holding circuit around the startingpush button PB. This holding circuit may be traced from the conductor2|, through the TOR. make-contact 25, and a back-contact TB of anauxiliary timer-relay TB, to a conductor 28, and thence through an "oil"drumcontact 29 of the emergency-drum ED, and through the TORmake-contact 28, to the TOR relay-terminal 23. The conductor 28 is alsoutilized to energize the actuating coil oi an interlock-relay IR, asshown at 3|, and also to enerelse other circuits which will be describedlater on.

Beiore actuating the starting-button PB to energize the take-oil relayTOR, the direction-selecting drum DD will ordinarily be actuated toeither its "west or "east" position, although the direction-selectingdrum DD could be moved subsequently to the energization of the take-0drelay TOR. This direction-selecting drum DD has two contact-members 32and 33 which are e1- i'ective in its "west" position, and twocontactmembers 34 and '35 which are effective in its "east" position.

The picking up of the third contact 21 of the take-oil relay TOR servesto energize the actuating coil of either the west or "east"contactor-switch W or E, according to the position oi the direction-drumDD. A partial circuit for these contactor-relays W and-E may be tracedfrom the conductor 2|, through the TOR makecontact 21, and back-contactsTRI and TR2 oi the two track-relays TR! and TR2, to a conduetor -36, andthence through a make-contact 81 of the speed-responsive relay 8|. to aconductor 31. which leads to a correspondingly numbered contact-point 31on the drum DD. 11 the drum DD is in its "west position, itscontact-member 32 energizes a contact-point 38, from which acorrespondingly numbered conductorJB leads, through an oil drum-contactnot .the emergency drum ED, to a conductor 40, from which a circuit iscompleted to the operating coil of the main contactcr W, through aninterlocking back-contact E of the other main oontactor E. It thedirection-drum had been in its "east" position, its contact-member :35would have Joined the contact-point 31 to a contact-point 4 I, whichleads, through 9. correspondingly numbered conductor M, and through an"foil" ,drum-contact 42 .of the emergency-drum ED,-to a conductor 43,which energizes the contactor coil E through a back-contact W or thecontactor W. I

.The conductor 31 is utilized also to energize the operating coil of thefirst field-controlling relay Fl, in a circuit which can be traced fromthe v.iiimductor 31, .through parallel-connected wandE. to aeondudor-Mmnd thence through a back-contact Fl of saidileld-relay-'-Fl,=m a conductor 45, and thence-through a make-contact-IRotthe interlocksrelaym, to a conductor 46, which energizes the operatingcoil ot=the fieldrelay Fl. The held-relay -Fldmmecliately seals itselfin. in a :circuit whicn-canbe traoed 1mm the relaying conductor 28,through a make-contact "Fl voi said fleld-relayiFl- -to dheicondnotor 45whichenergizes the operating coil Fl-through memake-icontact-IB and therelayingcimuitl'afi. I'he'eflectoi the energization of this field-relaFi is-to increase the excitation-oi :the three-phase generator .8,changing thevlexeitation from its minimum; value which it had with :allthreemi the fleld-resistorsB-L R2 and R8 incircilit. and causing the.tleldaexcitation ;to increase to a ilfllue :to .only two oiihe(field-re istors R: smell in theexcitins circuit :0! the s llerator. .Itis noted-that this increase .in thelgencrater-excitation occurs only,after, and ingesponse to; t emic g up -.or completed re onse of one ofthe main motor-starting contactors W or E from the, same control-circuit.31 which; is also .utilized to energize the-neld-rela -,F'|.

.Since the generator flux cannot v.chilIlBe instantly, in response to-anincrease inits excitingfleld current, but changes .on1y- K dl1%-Y,.according to the time-con tant or the genera or, this mode of.fieid-circw; con rol insures that the generator-voltage shall start outat .a.,-1ow value, upon the initial energization of the towinsacar motor3, thereafter increasing according to .the time-constant oi thegenerator-field, ii thejieldrelay F1. is .qulck in its .operat10n,..0rinvolvingany slowness ,oi' action, or other time-delay (litany) whichmay be built into the field-controlling relay Fl, as will be readilyunderstood ,by those skilled in the art. .It will be read l understood,oficourse. that other, and more elaborate; ileldcontrol means may be;utilized..10r cutting. out the field-resistancea-Rhfl and/or. B3 intwo, or-, more steps, ii desired, and in any desired time -sequence.myriad-contro ing mea s bein i ten ed to be broadly indicative 01 anysuitable ,vqlt age-increasing means for increasing :thevoltage ofthemupply-icircuit II, .or the output-term ll .01 .thegeneratori,atter=the initialenergizationoi the, motor 3.

'When the field-relay :Fl picksrl n. 28 make-contact :Fl closes abypass-circuit around'thespeedresponsive 1contact ,sL, circuit can betraced irom the conductor 38, through the field-relay contact Fl, .to aconductor .41,.-and thence-:thmuah 1a ake-contact oritherme -west";=or'iteas ,contector W or E. ,as the may -:be.. :to the conductor .31.:thereb by sing 11118; speeddeaponsive c tact Bi.-

bypassing circuit thus -assures ,the maintenance of ,the energization ofthe main contactor W or E throughout the aircraft-launchingaccelerating- ,run;oi the towing-O r I, even though the large amount ofenergy which is withdrawn from the generator I should cause theprime-mover shaft I to slow down below the point at which thetachometer-contact it-will be maintained. the speed-responsive relay SIbeing dependentupon said tachometer-contact l2.

v'Ihe towing-car l isnow well started onits aircraft-launchingaccelerating run, and the .automatic.controls are locked in, so thatwill .normally be completed. regardless or the starting pushbuttonIPB,or of the speed-responsiverelay-contact'sl. a

The acceleratingrrunoivthe-towing-car I conmake-contacts W and!!! of themain contactors "ll 'tinues'until timeout-reaches aweviouslyeelectodatoaic'e position along the trackway, at which time one of thetrack-relays TRI or TRZ becomes energized from the selected one of thetrack-transformers TRB to TR28. The response of the trackrelay opens itsback-contact in the energizingcircuit for the conductors 36 and 31, thusdeenergizing the main contactor W or E, whichever one was energized.

When one of the track-relays TR] or TR2 responds, it also closes acorresponding make-contact TRI or TRZ, which is to be found in serieswith the operating coil 01 an auxiliary timerrelay TA, in a circuit 48which is energized from the relaying conductor 28. This circuit may betraced from the conductor 28, through the auxiliary timer-relay coil TA,and thence through either one of the make-contacts TRI or TR2, which areconnected in parallel with each other, to the conductor 48, and thencethrough a makecontact 1B of the interlock relay IR, to a conductor 49,and to correspondingly numbered drum-contacts 48 and 49 oi thedirectiondrum DD.

If the direction-drum is standing in its west position, the drumcontact-member 33 connects the point 49 to the conductor 4|, whichenergizes the "east main contactor E, as soon as the previouslyenergized "west" contactor W drops out and closes its back-contact W. Ifthe direction-drum DD had been standing in its "east position, the drumcontact-member 34 would have connected the contact-point 49 to theconductor 38, which would energize the west" main contactor W, as soonas the east main contactor E opened its main contacts and closed itsbackcontact E. The effect, in either case, is to plug-- reverse thetowing-car motor 3, by applying power thereto in the reversephase-sequence. It will be understood that the towing-line or cable 2 iscast off from the launched aircraft (not shown) as soon as thetowing-car motor 3 is plug-reversed, the towing-cable connections beingsuch that the towing-cable is released by the aircraft when it soarsahead of, or above, the towingcar I.

The auxiliary timer-relay TA, which has been energized in thisplug-reversing process, picks up its make-contact TA and energizes thetimer T from its GO-cycle source 24. This timer T can be set to closeits contact T at the expiration of any predetermined time-interval,which is usually chosen to be such as to leave the full reverse power onthe car-motor 3 long enough to bring it to standstill and to start thecar moving back, towards its starting-point, the timing being chosen,however, so that the car will not have accelerated to a dangerously highspeed, in the reversed direction, at the expiration of the preselectedtime-setting of the timer T.

It will be recalled that the track-relays TR! and TR2 areposition-maintaining relays, which remain set in whichever position theyoccupy, even after the removal of the force or impulse which caused therelays to move to that position. At least one, and usually both, of thetrackrelays TRI and TR2 will now be "set" in their actuated position,responsive to the pre-selected one, or two, of the track-transformers T8to T28.

As shown at the bottom of the drawing, these track-relays TRI and TR2have additional makecontacts TRI and TR2, which are connected, inparallel with each other, to complete a circuit from the auxiliarycontrol-bus to a conductor and thence through the timer-contact T. whichcloses at the expiration oi the pre- 8 selected time-interval, as Justdescribed, energiziing a conductor 52 which energizes the operat ingcoil of the auxiliary timer-relay TB.

This auxiliary timer-relay TB instantly picks up and closes amake-contact TB which provides a "holding" circuit around thetimer-contact T, between the conductors BI and 52, so asto hold thisauxiliary timer-relay TB in its energized position. At the same time,said relay opens its back-contact TB which deenergizes the circuit 28which had been maintaining a holdingcircuit for the take-01f relay TOR,thus deenergizing this take-ofl relay TOR, assuming that the startingpush button PB has meanwhile been released or opened. The deenergizationoi the relaying circuit 28, in response to an energization of theauxiliary timer-relay TB, also results in the deenergization or thefield-relay holding circuit 28--Fl45, and in the deenergiz--' ation oithe interlock relay IR, thus again opening the field-relay circuit at45--IR46, de-

cnergizing the field-relay FI, and at the same time opening theplug-reversing circuit at 48- IR-49, thus deenergizing the maincontactor E or W, as the case may be, and discontinuing thereversed-phase-sequence energization of the towing-car motor 3, andusually leaving the towing-car coasting more or less slowly back towardits starting-point.

At this point, the operator usually takesover, with the aid of aspotting-switch S, which is energized from the relaying conductor 2|which remains energized after the take-oil relay TOR is deenergized. Thespotting-switch SS, has a central ofi" position, and west and "east"posi-; tions which energize the conductors 40 and 43, respectively,which in turn respectively energize the "west and east" main contactorsW and E.

It will be noted that the energization of the towing-car motor 3, whichis effected by, the spotting-switch SS, is at a low voltage, because thefield-relay Pl was deenergized, simultaneously with the discontinuanceof the automatic operations, prior to the manipulation of thespotting-switch SS. L1 this way, because of the reduced voltage, onlysmall amounts of power are fed into the towing-car motor 3, in thenormal manipulation of the spotting-switch, in order to give theoperator an accurate control over the towing-car, enabling him to bringit back to its starting-point, and accurately spot" it in any desiredposition.

The spotting-switch SS is provided with second "west" and "east"positions, however, in which the respective conductors 40 or 43 arestill energized, but additional contact-points 53 or 54 are engaged,energizing the conductor 46 which energizes the field-relay Fl, thusincreasing the field-excitation, and hence the generatorvoltage, toprovide more power, when necessary in the "spotting" control of thetowing-car I.

The take-oi! relay TOR, the control-drums DD and ED, and thespotting-switch SS, cooperate with the east and westreversing-contactors or power-switches E and W, to constitute relativelystationarily located control-means, by which I mean that thecontrol-means is stationary or non-movable with respect to thetowing-car while the towing-car is moving, without intending to implythat the control-means may not be portable or movable independently ofthe towing-car.

In the operation of my invention, as thus far described, provision ismade for the automatic "of!" position.

9 control oi the airerait-iaunchlng. acceleratingrunoi the towing-car I,in such manner as to cause the car to accelerate through a predeterminedlength of run, or distance along the runway, or to a predeterminedcar-position along the runway, after which the accelerating energizationof the towing-car is automatically discontinued, and the car isplug-reversed in ordarto quickly bring it .to standstill, or eventaslightly reverse its speed, without requiring any more length ofrunway than necessary, in the stopping process. The operation .of thisautomatic control has been outlined, during. the p ress 01 thedescription. so that no further summary is believedto be necessary.It.may be noted that I have thus provided a position-responsive ordistance-selectiveautomatic control which necessitates the utilization01 .only a single track-relay TRI or TR2, or the two trackrelays can beutilized, one to supplement or saiev guard the other, if desired, asalready explained.

Another. important feature of my improved control involvesthe use of theemergency-drum ED, the construction-and operation of which have not yetbeen described, except in connection with the three interlocks 29, 39and 42 which are closed when the emergency-drum ED is in its When theemergency-drum ED is-in itsl fwest position, it has acontact-member-towwhich. connects the contact point 55 toa-contact-point 51. The contact-point is connected to the normallyenergized relay-circuit 2i, while the contact-point 51 is connected tothe: relaying conductor 40 which energizes the west' mai-n contactor W.In the "east" position of .the emergency-drum ED,.a movablecontactmember connects the contact-point 51 at contact-point 59, whichis connected to the relaying conductor 43 which energizes the "east"main contaetor- The emergency-drum ED also has other "west and -feast"contact-members Bland-82, which connect the contacbpoint 83 to.contact-points 64 and -65,-preierably. in-steps, first connecting thepoint 64,--and-then, as the movement or the emergency-drum is continuedstill further away from its ofl" position; connecting the contactpoint85. The-contact-point 611 connected to the.--normally'energized relayingconductor 21. The-.contact-point 84 is connected to the relayingconductor 48, which energizes. the field-relay Ft;.-i'or increasingthevoltage applied. to the towing-car motor 3. The contact-point 65. isconnected to a similarly numbered relaying con- 4 ductor 65,which-energizes thesecond field-relay F2, for. short-circuiting-thesecond field-resistanoe R2, andstlll further increasing-theexcitationvand the output-voltage: or the. generator. 8.

The fleld-contwiiihg euzitactmembers "and izioi'ethe-emergency-drumEDmay preferably be stepped back,. with relation' tothecents-storcontrolling contact-members- 58 and Bit-=0! the a drum, sothat the contactor W or .E is first energized alone, without anyenergizationoi thefleldrelays Ft um, and then,- entire-movement oithmemergency-drum. is continued, further away -.irem.its oilfipoeition.contact is made, first with the contact-point 84-,- whichenergize; thefirst fleld-relayrFl. and then with the. contact-point mwhichenerglzesthe second field-relay F2. It willibe-understood, .01. course,thatvarlations in the precise-detailed thesearransemerrts-may bemademithirntheiskilloi theskilled. worker..

In theinormateincrait-latmchingi operation .of the electric catapult,the emergency-drum-ED4s notutillzed. When the oillcerin charge initiatesan aircraft-launching run, or sets the stage for such initiation, bydepressing the push button PB or equivalent starting-means, he keeps onehand alertly on the emergency-drum ED, ready to move it instantly, inthe event of any mishap 01 any nature.

As soon as the operator moves the emergencydrum ED out oi its "oil"position. in either direc, tion, he breaks the interlocking circuits 29,39 and 42, thus locking out the automatic-controlequipment. The.interlocking "01? position drum-contact 29 breaks the holding-circuitofthetake-ofl relay TOR, when the emergency drum is moved to. either its"west" or "east" position thus deenergizing the take-oil relay TOR,assuming that the push button PB has meanswhilebeen released or. opened.Iniike manner, the. emergency-drum contacts 39 and .deenergize theautomatic control-circuitaior the "west" and.east" main contactorsw andE,

whenever the emergency-drum ED is moved,in either direction, away fromits "oil" position. When these interlocking emergency-drum contacts 29.38 and 42 are once opened, the take-oil relay TOR is thus deenergized,and no further automatic control-operation will be obtained thereafter,even though the emergency-drumED is returned again to its "oil!"position, because, of theopeningot theTOR contacts 25 and 21., whicheiiectually lock out any further automatic operations, on thatrun.

Theenerglzation oi the towing-car motor-ails thereupon under the solecontrol of the emergency-drum ED, the motor being energized only when,and as long as, the emergency-drumlill) is held ineither its "west" orits "east position. After the operator has controlled the energizetion01' the towing-car motor, in any desired mannerrby the manipulation ofthe emergency druznED, he.wil1 usually-bring the car to astop, or atleast to arelatively slow speed, bymeans oi the emergency-drumaiterwhich the. operator may either utilize. the emergency-drum itseli as aspotting-switch, or he may change over tothe spotting-switch SS, andutilize the latter to bring the.car-back, to a controlled spot ateitherlend o1th'erunway..

While I have illustrated my invention in a single preferred form ofembodiment, I wish it tobe understood that many features of suchillustration are. only symbolic, and many interlocks and othercomplications, such as would normally-be utilized, have been omitted, inthe interests-oi eIarityoi illustration and explanation. I desire.therefore, that the appended claims shall be accordedthe broadestconstruction consistentwith their language.

I claim as my invention:

1. An electrically controlled system, comprising an electrically drivenself-propelled movable body. atrackway therefor, electrical supplymeanstherefor. and a relatively stationarily located control-mean therefor,characterized: by said control-means comprising run-controlling16188911188118, :a plurality of position-responsive pmeansydisposedat-apluralityoi positions along the=trackway, for developingrelaying-energyat each of their several positions during the-progress or: a forwardrunoi the movable body. pro-selector means for making therelaying-energy o1.-a pre selected'one or more or saidposition-responsive meansieflectively available in saidrun-controlhhmrelawmeans, to the substantial exclusion 76- of all others6! the position-responsive means, tor

actuating said run-controlling relay-means only in response to saidpre-selected position-responsive means, means for initiating a forwardrun of the movable body. and means for terminating said forward run inresponse to an actuation of said run-controlling relay-means.

2. An electrically controlled system, comprising an electrically drivenself-propelled movable body, a trackway therefor, feeder means forsupplying electric propulsion-energ to the movable body at each of aplurality of points distributed all along the trackway, and a relativelystationarily located control means for said movable body, characterizedby said control-means comprising run-controlling relay-means, aplurality of current-responsive means for developing relaying-energy inresponse to a substantial flew of electric energy into the movable bodyat each of a plurality of said points where said electricpropulsion-energy can be supplied to said movable body, pre-selectormeans for making the relaying-energy of a pre-selected one or more ofsaid current-responsive mean effectively available in saidrun-controlling relay-means. to the substantial exclusion of all othersof said current-responsive means, for actuating said run-controllingrelay-means only in response to said pre-selected current-responsivemeans, means for initiating a forward run of the movable body, and meansfor terminating said forward run in response to an actuation of saidrun-controlling relay-means.

3. The invention as specified in claim 1, characterized by said movablebody being polyphasemotored, said supply-means being polyphase, and saidrun-terminating means being adapted to energize said movable body in areversed phasesequence in response to an actuation of saidruncontrolling relay-means.

4. The invention as specified in claim 2, characterized by said movablebody being polyphasemotored, said feeder-means being polyphase, and saidrun-terminating means being adapted to energize said movable body in areversed phasesequence in response to an actuation of saidruncontrolling relay-means.

5. An electrically controlled system, comprising a self-propelled,polyphase-motored movable body, variable-voltage supply-means therefor,and a relatively stationarily located controlmeans therefor,characterized by said controlmeans comprising main starting-contactorsfor v energizing said movable body from said supplymeans in the onephase-sequence or the other. starting-means for selectively energizingone of said contactors to initiate a forward run of the movable body ina selected phase-sequence, and means responsive to a completed responseof said selected contactor for effecting an increase in the voltage ofsaid supply-means.

6. The combination with a trackway, and electrical supply-meanstherefor, of control means comprising automatic relay-means, a pluralityof position-responsive means, disposed at a plurality of positions alongthe trackway, for developing relaying-energy at each of their severalpositions during the progress of a movable member alon said trackway,pre-selector means for making the relaying-energy of a pre-selected oneor more of said position-responsive means eifectivelvavailable in saidautomatic relay-means, to the sub stantial exclusion of all others ofthe positionresponsive means, for actuating said automatic relay-meansonly in response to said pre-selected position-responsive means, meansfor initiating .the energization of said supply-means for the trackway,and means for automatically terminating the aforesaid energization ofsaid supplymeans in response to an actuation of said automaticrelay-means,

'l. The combination with a trackway, and sup ply-means for supplyingelectrical energy at each of a plurality of points distributed all alongthe trackway, of control-means comprising automatic relay-means, aplurality of current-responsive means for developing relaying-energy inresponse to a substantial flow of electric energy into the trackway ateach of a plurality of said plurality of points where energy issupplied, pre-select'dr means for making in the relaying-energy of apreselected one or more of said current-responsive means effectivelyavailable in said automatic relay-means, to the substantial exclusion ofall others of said current-responsive means, for actuating saidautomatic relay-means only in response to said pre-selectedcurrent-responsive means, means for initiating the energization of saidsupply-means for the trackway, and means for automatically terminatingthe aforesaid energization of said supply-means in response to anactuation of said automatic relay-means.

8. The invention as specified in claim 6, characterized by saidsupply-means being polyphase, and said automatic terminating-means beingmeans for automatically causing said supplymeans to be energized in areversed phase-sequence in response to an actuation of said auto"- maticrelay-means.

9. The invention as specified in claim 7, characterized by saidsupply-means being p lyphase, and said automatic terminating-means beingmeans for automatically causing said supplymeans to be energized in areversed phase-sequence in response to an actuation of said automaticrelay-means.

10. The combination with a polyphase supplyline, and a variable-voltagepolyphase ene'rgysource therefor, of control-means comprising mainstarting-contactor's for energizing said'supply-line from saidenergy-source in the one phasesequence or the other, starting-means forselectively energizing one of said contactors to initiate theenergization of said supply-line in a predetermined phase sequence, andmeans responsive to a completed response of said selected contactor foreffecting an increase in the voltage of said energy-source.

11. An electrically controlled system, comprising a self-propelled,polyphase-motored movable body, variable-voltage supply-means therefor,and a relatively stationarily located control-means therefor,characterized by said control-means comprising main starting-contactorsfor energizing said movable body from said supply-means in the onephase-sequence or the other, and'starting means operative to selectivelyenergize one of said contactors to initiate a forward run of the movablebody in a selected phase-sequenceand also operative to effect anincrease in the voltage of said supply-means.

12, The combination with a polyphase supplyline, and a variable-voltagepolyphase energysource therefor, of control-means comprising mainstarting-contaetors for energizing said supply-line from saidenergy-source in the one phasesequence or the other, and starting-meansoperative to selectively energize one of said contactors to initiate theenergization of said supply-line in a predetermined phase-sequence andalso operative to effect an increase in the voltage of saidenergy-source.

aeoaros 13. In combination, a poiyphase energy-clrouit, a polyphaseload-circuit, polyphase switchingmeans for connecting and disconnectingsaid polyphase load-circuit to and from said polyphase energy-circuit ina desired forward-'phasewe q ence, other switching-means for performingone or more other controlling operations ailecting said polyphaseload-circuit, operation-*presetting means for presetting the terminationof the forward-phase-seq-uence energization of the -polyphaseload-circuit, an operation-maintaining relay-means, starting-means -forinitially actuating said operation-maintaining relay-means, anoperation-relay 3 holding-circuit, responsive to the actuation ofsaidoperation-maintaining-relaymeans, for maintaining the actuation ofsaid operation-maintaining relay-means, forward-controlling means,responsive to the actuation of said operation-maintaining relay-means,for closing said forward-phase-sequence switching-means.forward-terminating means, responsive to the operation-presetting means,for opening said forward-phase-sequence switching-means, additionalcontrol-means. responsive to the opening of the forward-phase-sequenceswitching-means and F15 responsive also to a continued actuatedcondition of-saidoperation-maintaining relay-means, for setting inmotion some one or'more operations of said other switching-means,and'means; including a relay-contact in said operation-relay holdlng-.circuit, for interrupting said operation-relay holding-circuit after theconclusion ofthe operation.

14. In combination, a polyphase generator having a field-windingcircuit, a polyphase loadcircuit, polyphase switching-means forconnecting and disconnecting said polyphase load-circuit to and fromsaid polyphase generator in either the forward or reverse phase-mquence,field switching-means for performing a controllingoperation on saidfield-circuit, operationpresettlng means for presetting the terminationof-- the forward-phase-sequence energization of thepolyphaseload-circuit, an operation-maintaining relay-means, starting-means forinitially actuating said operation-mamtaining relaymeans;anoperation-relayholding-circuit,'-responsive to the actuation of saidoperation-maintaining relay-means, for maintaining the actuation of saidoperation-maintaining relay-means,- forward-controlllng means,responsive to the actuation of said operation-maintaining relaymeans,for closing said polyphase switchingmeans in a desired forwardphase-sequence, fieldcontrolling means, responsive to an actuated con--dition of said forward-controlling means and responsive also to an opencondition of saidi'ield switching means, for closing said-fieldswitchingmeans, a field-controlling holding-circuit; responsive to theclosing of said field switching-- means and responsive also to acontinued actu ated' condition of said operation-maintainingrelay-means, for maintaining the closed condition of saidfleld'switching-means, forward-terminating means, responsive to theoperation-presenting means, for opening said forward-controlling means,reverse-controlling means, substantially simultaneously responsive to.the operation-presetting means and responsive also to an open conditionof the polyphase switching'means in the forward phase-sequence,iorclosins said polyphnse switching-means in. the reversephase-sequence, reverse-power presetting-means for presetting thereverse-power operation, and reversetermlnating means, responsive to thereverse- 14 power-presetting-means, for-opening the polyphaseswitching-means and the fleld-controlllng holding-circuit, the apparatusalso including operation-terminating means; including: a relaycontact insaid operation-relay holding-circuit, for interrupting saidoperation-relay holdingcircuit after the conclusion of the operation;

15. In combination,- a self-propellin p0 5- phase-motored, movable body,a track therefor, a polyphase motor-energizing circuit which iscontinuously connected -to said polyphase-motoredbody. a polyphaseenergy-circuit, polyphase switching-means for connecting anddisconnecting said-polyphase motor-energizing circuit to and from-saidpolyphase energy-circuit in a desired forward phase-sequence, otherswitchingmeans for-performing one or more. other=controllingoperations-afl'eoting said polyphase motor-energizing circuit,track-relay means which is selectively responsive to a predeterminablepositionor the polyphase-motored movable body at any one-of-a pluralityof selectable'points along the track, operation-presetting means forutiiizing said track-relay means for terminating theforward-phase-sequence energization of the polyphase motor-energizingcircuit, an operationmaintaining relay-means, starting-means forinitially actuating said operation-maintaining relaymeans. anoperation-relay holding-circuit, responsive to the actuation of saidoperation-mamtainins relay-means, for maintaining the actuation oi saidoperation-maintainingrelay-means. forward-controlling means, responsiveto the actuation of said operation-maintaining relaymeans, for closingsaid forward-phase-sequence switching-means, forward-terminating means,responsive'to the operation-presettlng means, for opening saidrorward-phase-sequence switchingmeans, and additional control-means,responsive to the opening 0! the forward-phase-sequence switching-meansand responsive also to a continued actuated condition of saidoperationmalntainin'g relay-means, for setting in motion some one ormore operations of said other switching-means, said additionalcontrol-means including a timer-means, responsive to the initiation of apredetermined operation ofsaid other switching-means and responsive alsoto a continued responded condition of said track-relay means, forinterrupting said operation-relay holding-circuit, said timer-meansincluding a self-energized holding-circuit-which is responsive to acontinued responded condition of said track-relay means.

18. In combination, a self-propelling, polyphase-motored, movable body,a track therefor, a polyphase motor-energizing circuit which iscontinuously connected to said polyphase-motored body, a polyphaseenergy-circuit, polyphase switching-means for connecting anddisconnecting said polyphase motor-energizing circuit to and from saidpolyphase energy-circuit in either the forward-or reversephase-sequence, track-relay means'which'is selectively resitonsive to apredeterminable position of the polyphase-motored movable back at anyone of a plurality orselectable points along the track,operation-presetting means for utilizing said track-relay means-forterminating the i'orward-phase-sequence energization ofthe polyphasemotor energizing-circuit, an operation-maintaining relay-means,startingmeaus for initially actuating said operationmaintainingrelay-means, an operation-delay holding-circuit, responsive to theactuation of said operation-maintaining relay-means. for

maintaining the actuation of said operationmaintaining relay-means,forward-controlling means, responsive'to the actuation of saidoperation-maintaining relay-means, for closing said polyphaseswitching-means in a desired forward phase-sequence, forward-terminatingmeans, responsive to the operation-presetting means, for opening saidforward-controlling means, reversecontrolling means, substantiallysimultaneously responsive to the operation-presetting means andresponsive also to an open condition of the polyphase switching means inthe forward phasesequence, for closing said polyphase switchingmeans inthe reverse phase-sequence, reversepower presetting-means for presettingthe reverse-power operation, and reverse-terminating means, responsiveto the reverse-power presetting-means, for opening the polyphaseswitchingmeans, the apparatus also including an operation-terminatingrelay having a relay-contact in said operation-relay holding-circuit forinterrupting said operation-relay holding-circuit, saidoperation-terminating relay including a self-energized holding-circuitwhich is responsive to a continued responded condition of saidtrack-relay means.

17. In combination, a self-propelling polyphase-motored, movable body, atrack therefor, a polyphase motor-energizing circuit which iscontinuously connected to said polyphase-motored body, a polyphasegenerator having a field-winding circuit, field switching-means forperforming a controlling operation on said field-circuit, polyphaseswitching-means for connecting and disconnecting said polyphasemotor-energizing circult to and from said polyphase generator in eitherthe forward or reverse phase-sequence, track-relay means which isselectively responsive to a predeterminable position of thepolyphase-motored movable body at any one of a plurality of selectablepoints along the track, operation-presetting means for utilizing saidtrackrelay means for terminating the forward-phasesequence energizationof the polyphase motorenergizing circuit, an operation-maintainingrelay-means, starting-means for initially actuating saidoperation-maintaining relay-means, an operation-relay holding-circuit,responsive to the actuation of said operation-maintaining relaymeans.for maintaining the actuation of said operation-maintaining relay-means,forward-controlling means, responsive to the actuation of saidoperation-maintaining relay-means. for closing said polyphaseswitching-means in a desired forward phase-sequence, field-controllingmeans, responsive to an actuated condition of means in the reversephase-sequence, reversepower presetting-means for presettingthe-reverse-power operation, and reverse-terminating means, responsiveto the reverse-power presetting-means,-for opening thereverse-controlling means and the field-controlling holding-circuit,said reverse-terminating means including a selfenergized holding-circuitwhich is responsive to a continued responded condition of saidtrackrelay means, the apparatus also including an operation-terminatingrelay having a relay-contact in said operation-relay holding-circuit forinterrupting said operation-relay holding-circuit, saidoperation-terminating relay including a self-.- energizedholding-circuit which is responsive to a continued responded conditionof said track relay means.

18. The invention as defined in claim 15, char.- acterized by thetrack-relay means being of the retained-contact type having areset-coil, and the combination including reset-means for energizingsaid reset-coil.

19. The invention as defined in claim 16, characterized by thetrack-relay means being of the retained-contact type having areset-coil, and the combination including reset-means for energizingsaid reset-coil.

20. The invention as defined in claim 17, characterized by thetrack-relay means being of the retained-contact type having areset-coil, and the combination including reset-means for energizingsaid reset-coil.

21. In combination, a load-circuit, power-supply means therefor,automatic control-means operative, once it is set in operation, to carrythrough a predetermined series of a plurality of successiveswitching-operations affecting the power-supply to said load-circuit, aplurality of presetting adjustment-means for said automaticcontrol-means, a resetting means for resetting said automaticcontrol-means after the completion of its operation, anoperation-starting circuit for said automatic control-means, aholding-circuit for said automatic control-means, means including arelay-contact in said holdingcircuit for interrupting saidholding-circuit after the conclusion of the operation, and meansresponsive to a subsequent operation of said resetting means forreclosing said relay-contact in the holding-circuit.

RUEL C. JONES.

REFERENCES CITED The following references are of record in the file ofthis patent:

Great Britain Apr. 28, 1941

